Mechanical stoker.



`G. B.y RAIT- yPatented Aug'. 10, 1915.

.6 SHEETS-SHEET 1.

G. B. HAI

MECHANICAL STOKER. .APPLicATIoN FILED APR. 1o. 1914( .Patented Aug. 10, v1915@ G. B. RMT.

MECHANICAL ,STOKER- APPL|cATmN man APR. 1o. 1914.

Patented Aug. 10, 1915.

6 SHEETS-SHEET 3.

G. B. Rm. MECHANICAL STOKER.

APPLICATION FILED APR. l0. 19H.

Patented Aug. 10, 1915.

Z'z'wesses G. B. RMT.' MECHANICAL STOKER.

APPLICATION lFILIED APR. IO, 1914.

PntentedAug. 10, 1915.

6 SHEETS-SHEET 5.

t/)airways Pawnted Aug. 10, 1915.`-

6 SHEETSAHEU 6.

'G. B. RAIT.

MECHANICAL STOKER.

APPucATloN FILED APR.10.1914. 1,149,685.

TTM

GEORGE B. Barr, OF MINNEAPOLIS, MiNNsso'rA.

OFFICE.

iim'oHANcriL 'sroKE'ie To all @07mm it may concern :I v

Be it known that I, GEORGE B. Rari', a citizen of the vUnited States, residing at Minneapolis, in the county of Hennepin and State of Minnesota., have yinvented certain new and useful Improvements in Mechanical Stokers; and I dohereby declare the following to be a full, clear, and exact description of the invention, such as will enableothers skilled. in the art to which'it appertaiiis to make and use the same.

My vinvention has for its object to provide an improved mechanical stoker, especially adapted for use in connection with locomotives, and to such ends, generally stated, the invention consists of the novel devices and combinations of devices. hereinafter described and defined in the claims.

-In the accompanying drawings which illustrate the invention, likecharacters indi v cate'like parts throughout the ,several views.

Referring to the drawings: Figure 1--is a vertical section taken centrally through the stoler and portions of the engine tender and reboxof the engine boiler; Fig. 2 shows taken on nthe line :1:4 m4 on Fig. l; Fig; 5 is v a view corresponding very much in the line of section to Fig. 1, but showing the parts on y a larger scale, and with some parts shown in full and others broken away.; Fig. 6 is a transverse vertical section taken approximately on the -line m m0 on Fig. l, but with some parts' shown. in full and some parts broken away; Fig. T'is a detail in vertical section taken on the line af .07 on Fig. 2; Fig. 8 is a detail in horizontal section taken on the line m8 ics on Fig. 7:' Fig 9 is a view corresponding to Fig. 1, but illustrating a modified construction; FigQ 10 shows the engine tender in plaiiand the fire box of the vboiler in horizontal section; Fig. 11 is a fragnientary view in transverse vertical section'taken on the line 0311v fc on Fig. '9; and Fig. 12

- shows one of the coal deploying nozzles in horizontal section on the line x12' w12 on Fig. 11.

, In the accompanying drawings 1I, havev illustrated my invention embodied both in over-feed and underfeedl typen of Stoker.

Y 'So-far as ing feed bar such as that disclosed and Figs. 1 to 6, inclusive, and will first be `described: Thenumerals 1, 2 and 3 indicate, respectively, the engine tender, the engine cab, and the walls of the rebox of a locof ing bracket 7 secured on the bottom of the Specification of Letters Patent.b Patented Allg. 10, 1915. Appncanonieeiipriiio,1914. seriaiNo. 830,878. n

The over-feed construction is illustrated in i tender.l rllhe front end only of the feed hop- -per 6 is made cylindrical and is loosely telescoped into the receiving vend of an upwardly and forwardly curved fuel feed spout 8, and preferably, is rigidly, but detachablysecured by bolts, or otherwise, to a -liorizontallyfilaring delivery head 9 that is extended througha suitable opening-formed in the rearvwall yor rear water leg of the fire box j ust below its door opening 10. The bottom plate of this feed head 9 is preferably flat, so that it affords a feed table, and is provided with laterally curved fdeflecting ribs 11, and preferably also, with. a central delecting lug or divider 12. Thetable orbottom plate -of said feed head 9 is offset belowthe adjacent wall of the feedvspout 8 at a point where it joins therewith, and the said feed spout is there formed with a trans-` (see pajrticulfrlyv Figs. 1 to 5), that is centrally divided by a verse steamy passage 13 partition 14 (see Fig. 6). The outer extremities of the divided steam passages'lS are connected to 'steamblast pipes 15 that re-v ceive steam throughAvalve-controlled chamberg presently to be described. Each of the steam passages 13 deliver to one or more, as shown, each to two steam discharge nozzles 16 (see particularly, Figs. 2 .and 5). These nozzles 16 have forwardly iaringaxial passages and threaded Shanks which latterare screwed into seats in the upwardly projecting portion of the adjacent wall of the feed spout 8. It may be here stated that the axial passages of the nozzle 16 are made flaring,

so as to spread the blast of steam, and that the said nozzles may be made with different size bores and provided in sizessuitable for the particular size of fire box to which they are applied.

vices maybe employed in the feed hopper. 6. For example, I might employ a reciprocatthe present invention is con? 1cerned.various different rkinds of' feed de-A claimed in my prior Patent No. 1,085,630, of date February 3rd, 1914, but I have shown, and preferably employ a heavy and very strong spiral conveyer or feed screw 17, the shaft of which, at its rear end, is journaled in the rear end of the said hopper, and at its forward end is connected, preferably by a knuckle joint 18 tothe rear end of a short shaft 19 that is journaled in a sleeve-like bearing projected forward from the lower portion ,ofthe front wall of the feed spout 8.

In the present embodiment of my invention, I drive the spiral conveyer 17 from a small spiral toothed rotary turbine, such as that known to the trade as the Spiro and manufactured and sold by the Buffalo Forge Company. I do not, of course, limitmyself to the use of this particular motor, but for the application' thereof, I provide the short end of the front shaft 19 with a worm gear 20. Spiral rotors 21 of the said turbine work in asuitable casing 22 (see Figs. 1 to 5), which preferably, and as shown, are rigidly secured to the feed spout 8, and in addition to the steam chamber 23 in which the spirals 21 work, it is provided with gear -chambers 24; and 25 (see Figs. 5 and 6).

Live steam from the boiler is used to operlate the above described turbine, and such steam is delivered thereto through a steam .supply pipe 26. This steam lpi Je 26 leads from a steam turret or header 2 that is in communication with the boiler and certain other devices not necessary to note. The delivery end of the steam pipe 26 (see Fig. 5) delivers live steam to the steam chamber 23 of the turbine, through small diverging ports28. The said steam chamber 23 delivers the exhaust steam at opposite sides to exhaust pipes 29 (see Figs. 1, 2 and 3), and these exhaust pipes 29 lead to opposite sides of the fire box and will independently connect each to a plurality of combined air injectors that open through the sides of the lire boX at points above the grate 80 and above the ire. These air injectors are shown in detail in Figs. 7 and 8, and as preferably constructed, they comprise shorttubes 31 that extend through the laterally spaced walls of the lire 'Tubular air intake elbows 32 extend iiit the tubes 31 and, as shown, have dependingopen ends and auxiliary air intake ports 33. `The exhaust pipes 29 extend through the elbows 32 and inside thereof, are provided with steam discharge nipples 34 that direct the steam axially through the tubes 31 and draw in the air through the elbows, so that amixture of air and steam will be discharged into the firebox above the fire and will very greatly intensify the combustion and eliminate or very greatly reduce 'the smoke. While it is not broadly new to; inject air and steam into a rebox, I believefhowever, that 1t is broadly new first to utilize steam to operate a feed motor and then to utilize the exhaust steam from the said motor for the purpose above noted, and this feature I desire to broadly claim. i

)Ve will now describe the way in which theiturbine above noted is utilized both to drive the spiral feed screw or conveyer 17 and to intermittently. control the discharge of steam through the nozzles 16 for the purpose of spreading or deploying the coal over the grate or within the iirebox. Directing attention iirst to Fig. 5, it will be noted that the shaft of one of the spiral toothed rotors 21 of the turbine is provided with a spur pinion 35 that meshes with a spur gear 36 secured on the counter shaft 37 (see Fig. 6) journaled in suitable bearings on the motor casing. and provided with a worm 38, which, in turn, meshes with the worm gear 20 secured on the front end of the supplemental shaft 19 of the spiral conveyer 17. By these connections. as is obvious, the feed' screw or conveyer 17 will be continuously rotated whenever the turbine is in action. but of course, at a comparativeliv low speed. Here it mav also he noted (see Figs. 5 and 6) that the hub ofthe worm gear 39 carries a cam 40 that engages a downwardlyv spring-pressed cross head 41.

The cross head 11 is connected to the depending ends of the stems of 'thewv'alves' 42.

that normally close ports in independent or separated steam chambers 43 formed in the motor casing. as best shown in Figs. 5 and 6. The upper portions of these steam chambers 13 are connected to the deliveiw ends of steam pipes Jf-l that are connected o a threeway coupling 15 (see Fig. 3) that is equipped with a three-way valve #16 of well known constructionY This coupling L15 is connected bv a short pipe 17 to the steam pipe 26. but it might. nevertheless he independently con'- nected to the boiler. Just above the threeway valve 16 and the pipe L7 is preferably also provided a cut-ofi valve 48, and the steam pipe 26 below the point where it is tapped by the pipe 1T. is also preferably provided with a cut-off valve 49. It may be here noted that the steam pipe 26` as shown, is provided at its receiving vend with a cut-off valve 50.

The lower portions of the two valve equipped steam chambers i8 are independently connected to the two steam deliveryA pipes 15 above noted. and which it will b'e remembered are independently connected to the two steam chambers 13. `which chambers discharge through different pairs or mem-V Referring particularly to Figs. 1 and 4.

` it will be noted that the hopper passages 5 are arranged to be opened and closed at v will by cover plates52 that are arranged to slide 1n guide-ways 53 formedin the sides of the bottom of the` floor a yof the coal ously to both sides of the rebox', or at will,

:it may be delivered to either one side thereof.

bunker or space 4.- The arrangement and operation of' thesecover plates is more fully set ,forth and broadly claimed in my prior. patent, above identied,land hence, for the purpose of this case, it is only desirable 'to state that by sliding th'e cover lates forward, one after the other, as tie coal is fed from. the bunker, a supply opening into the' feed hopper 6 may be always maintained at the proper point. Underlying the cross or transverse portions of the hopper passages 5 and rigidlysecured on top of the hopper' are crushing bars 54'ag`ainst which large lumps of coal will be forced and crushed by the action of the feed screw or spiral 17 Operation: The operation summarized, is

substantially as follows: The coal from the bunker '4 will fall by gravity through the open upper passage 5 into the hopper 6 where it will be taken up by the spiral-conyeyer 17 andv positively forced forward and into the receiving end 'of the Jfeed s out -8.

By the crowding action of coal 'de ivered 'into the lower end of said feedspout 8, the

coal will be forcedupward through the said spout 'and Ontol the table of they feedhead f -9, andvin fact, the. coal would be forced inward, into the lirebox through the said feed head, solely by the said crowding action, were it not for another and very highly important action produced by the blast v from the nozzle 16. Some ofthe coal mayv ful be simply crowded' through the said 'feed head into the fire box, but the greater part thereof will be blown into the 'fire box and spread out or deployed -therein by'p'owercam 40, once for eachl rotation of the spiral 'conveyor 17. Obviously, whenever the said valves 42 are opened, as shown in Fig. A6,

` live steam from the boiler will rush-through the steam pipes 44, chambers 43 and pipes l5 andchamber's 13, to the said nozzles-16,

'thereby producing violent puffs or` steam blasts suflicient to blow the lumps of coal to any part of the'firebox. The converging ribs 11 tend. to spread the coal laterally within the .irebox The intensity ofthe blast Vproduced when theI said valves 42 'are opened may be regulated by opening or closing more or less the valve 48 in the pipe section 47. Byl means of the three-way valve 46, the blast miay'be'directed through both ot' the pipes 44, or through either one.

thereof, at willa AIn this way, the 1blast may be simultaneousl)v delivered to both pairs of groups of nozzles 16,01' 1t may be delivered intermittent steam blasts delivered solely to the nozzles on one side of the feed head. By these regulations' .of the' blast, coal may, therefore, be delivered simultane- In this way, therefore, coal may be delivered at any place in the reboX, so as to keep the fire properly built up and the coal properly distributed. l The steamturbine and hence, thel spiral conveyer or feed 'screw 17, will be kept in laction as long as the valve 49 is opened.

In all of the above described operations', it is, of course, assumed that the valve 50 is opened. The said valve A50, when closed, will, in the arrangement described, cut oi lall supply of steam to the various steam fis rendered available at the very time that coal is supplied tothere box, and at which timethe additional supply of air is required' to support combustion and to prevent the escape of .dense smoke and, consequently, waste ofl fuel. Otherwise stated, the supplylof steam and air into the irebox from I the inf'ectors is automaticl with the supply.

of fue The underfeed structure illustrated in F igs.,9 and 10, 11 and 12, is identical with Vthat, above described with the following exceptions.l The feed spout 8 opens through the bottom of the irebox 'and terminates slightly above theV grate 3 1 thereof, andhas separated steam chambers 13a thaty correspond to the chambers 13 and each of these chambers 13a is. provided with three for- -wardly converging steam discharge nozzles 16a that arearranged tov blow forwardly converging blasts of steam directly over the irebox grates. All of the other elements of this underfeed device .are substantially lidentical with' that of the overfeed device ypreviously described, and hence, corresponding elements are indicated by like characters, so that they will be'understood by thelreading ofthe description of said overfeed device.

Vhat I claim is: i 1. The oombinationwith a boller having a fire box.- of. a `mechanical stoker comprising a fuel feed device delivering into said y iirebox, a steam motor with connections .for operating said feed device,the said motor having connections `for delivering live steam thereto from said boiler and having kexhaust connections, including air intake devices, for delivering commingled exhaust steam and air into said fire box, the delivery 'of the fuel and exhaust steam and air into saidiire box being timed in respect to each `other by the operation of said motor.

2. The combination with a boiler having y a firebox, of a mechanical Stoker comprising a fuel feed device delivering into said fire- `1o box, a steam actuated motor for operating said feed device, said motor having connections for supplying the same with steam from said boiler, and having duplex Iexhaust connections directing the exhaust steam into the opposite'sides of the rebox,

the said exhaust connections including air intake devices for delivering air commin led with the exhaust steam into the said lire ox.

3. The combination with a boiler having :2,0 a iirebox, of a mechanical stoker comprising a fuel feed device delivering into said fire- -box, anda steam turbine with connections for operating said feed dev1ce,.said turbineincluding air intake devices whereby commmgled air andexhaust steam will be introduced into said fire box.

4. The combination with, a boiler having a lire box, of a mechanical stoker comprising a fuel feed device delivering into said fire box, a steam motor with connections for operating said feed device, said motor having connections for delivering live steam thereto from said boiler and having exhaust connections for directing the exhaust steam therefrom into said lire box, a live steam de- 40 livery'nozzle located at the place of delivery of the fuel-into said fire box, and live steam s delivery connection from said boiler to said live steam delivery nozzle, including a valve operated by said motor, whereby the deliva5 ery of fuel, and of live steam and exhaust pulsations into said fire box, are timedin respect to each other. Y

5. The combination with a boiler having a iir'e box, of a mechanical stoker compris- 5o ing a fuel feed device delivering intosaid fire box, a. steam motor with connections for operating said feed device, the said motor having connections for delivering live steam thereto from said boiler and having exhaust v connections for directing the exhaust steam therefrom into said ire box, opposed live steam blast delivering nozzlesdocate'd at the placel of delivery of the fuel into said lire box, and alive steam delivery connection .so from said-boiler` to said nozzles, including a valve operated by said motor, wherebyl the.

delivery of fuel, and of the live steam fand exhaust pulsations into the said ,fire box are' timed in respect to each other.

c5 The combination with-a boiler having a fire box, of air-mechanical Stoker comprising Y a fuel feed device delivering into said iire box, a steam motor with connections for operating said feed device, said motor having connections for delivering live steam thereto from said boiler and having duplex exhaust connections, including air intake devices, for delivering commingled exhaust steam and air into said fire box, live steam blast delivery nozzles located at the place of delivery of fuel into said fire box, and live steam delivery connections from said boiler to said blast nozzles, including valves operated by said motor, whereby the delivery of fuel and of the live steam and exhaust pulsations into said fire box are timed in respect to each other.

7. The combination with a fire box, of a `mechanical Stoker for deliverying fuel into said'fire box, opposed blast delivery nozzles located at the place of delivery of the fuel into said fire box and arranged for deliverv of the fuel to opposite sides of the fire box, a three-way valve, a steam supply pipe leading from said boiler to said three-way valve, and branch pipeslead'ing from said threeway valve to said opposed nozzles, whereby, by manipulation ofy said three-way valve, the said opposed nozzles may be thrown into action simultaneously, or at different times.

8. The combination with a irebox, of a mechanical Stoker for delivering fuel into said firebox, blast delivering nozzles located at the place of delivery7 of the fuel into said iirebox and arranged in two groups for delivering of fuel to opposite sides of the firebox, a three-way valve, a steam supply pipe leading from the boiler to said three-way valve, and branch pipes leading from said thiee-way valve to the two groups of nozzles, whereby; by manipulation of the threeway valve, the said two groups of nozzles may be thrown into action separately, or both groups simultaneously.

9. The combination with a firebox, of a mechanical stoker for delivering fuel into said irebox, blast delivering nozzles located at the place of delivery of the fuel into said irebox, and arranged in two groups for dee livery of fuel to opposite sides of said firebox, a three-way valve, a steam supply pipe leadin to said three-way valve, a cut-od valve in said steam supply pipe for regu- .lating the pressure of said steam supply for blast purposes, and branch pipes leading from' said three-way valve to the two groups of nozzles whereby by manipulation of said three-way valve the-said two groups of nozzles may be thrown into -action separately, or both groups simultaneously.

. l0. The combination with a firebox, of a mechanical Stoker for delivering fuel into said irebox, blast delivering nozzles located at. the place of delivery of the fuel into said irebox and arranged in two vgroups for delivery of fuel to opposite sides of said rebox, a three-way valve, a steam supplypipe leading to said three-way valve, and branch pipes leading from said three-way valve to the two groups of nozzles for blast purposes whereby by manipulation of said threeway valve, each side of the irebox may be fired separately,- or both sides simultaneously.

11. The combination with a rebox, of a mechanical Stoker for delivering fuel into said lirebox, blast delivcrin nozzles located at the place of delivery of t e fuel into said irebox and arranged m two groups for delivery of fuel to opposite sides of said lirebox, blast delivering valves leading into said blast nozzles, said blast delivering valves being actuated by a cam on the forward end of the main shaft of the spiral conveyer, a three-way valve, a steam supply pipe leading to said three-way valve, and branch pipes connecting said three-way valve and said blast delivering valves and nozzles, whereby by manipulation of said three-way valve, the said two roups of blast delivering valves and nozz es may be thrown into action separately or both groups simultaneously.

12. The combination with a rebox, of a mechanical stoker for delivering fuel into said firebox, blast deli vering valves and noz` zles located at the place of delivery of the fuelinto'saidrebox, and arranged in two groups for delivering fuel to opposite sides of said irebox, said blast'delivering'valves y being actuated by a cam on the front end of the main shaft of the spiral conveyer, a three-way valve, a steam supply pipe leadying to said threefway valve, and branch GEORGE B. RAIT.

Witnesses ERA E; KNIG,

HARRY D. KILGOR'E. 

